In recent years, servers and information communication devices have been widely spreading to support a social infrastructure, but the power consumption thereof increases and the need for reducing this increases. Therefore, in the field of telecommunications carriers and data center operators, the following DC power feeding system is known. An AC power supply is converted to high voltage of, for example, DC 380 volts (hereinafter, referred to as DC 380 V) to supply power with high voltage, whereby load current is decreased and thin wires can be used. Thus, the installation cost can be reduced. In addition, by adapting loads to DC 380 V and to high voltage DC power feeding, power loss due to DC/AC conversion and DC/DC conversion is reduced, whereby energy saving is achieved.
In this field, servers and communication equipment which are loads are being increasingly adapted to DC 380 V. However, for example, in the case where there are AC loads such as an air conditioner, fire-fighting equipment, and an existing server that cannot be adapted to DC 380 V, power of DC 380 V is converted to AC power by a DC/AC conversion device and the AC power is supplied to these loads. In addition, in the case where there are loads such as DC-48-V loads and DC-12-V loads other than DC-380-V loads, power of DC 380 V is converted to voltages adapted to the respective loads by DC/DC conversion devices, and the converted voltages are supplied. In particular, in this field, the DC/AC conversion device and the DC/DC conversion device are called migration devices.
One example of such devices is disclosed in Patent Document 1. In Patent Document 1, an electronic device having a circuit configuration shown in FIG. 3 of Patent Document 1 is mounted, as shown in FIG. 4, in an electronic device storage box in which electronic devices such as an exchange device and an optical fiber termination device are to be mounted.
As shown in Patent Document 1, conventional standard electronic device storage boxes are storage boxes of JIS standard and EIA standard which are called 19-inch rack.
A migration device 4 formed with a 19-inch rack as an electronic device storage box shown in FIG. 4 of Patent Document 1 is configured as shown in, for example, FIG. 1B of the drawings of the present application. The electronic device storage box is composed of a pair of box bodies, and one of the box bodies stores: communication electronic devices EM (DC) of DC-driven type such as a router and a switching hub; a DC/AC converter CV (AC) of AC-driven type; and a rectifier RF for performing DC power feeding. The other box body stores: communication electronic devices EM (AC) of AC-driven type such as a firewall; and four servers SV (DC) of DC-driven type.
As shown in FIG. 3 of Patent Document 1, a commercial power supply is converted to DC power through AC/DC conversion, and then the DC power is directly supplied to DC loads, and meanwhile, for AC loads, the DC power is converted into AC power through DC/AC conversion and the AC power is supplied to the AC loads. Even in the case of DC loads, if, for example, a power supply is DC 100 V but the load is adapted to DC 48 V, the power supply is converted to DC 48 V through DC/DC conversion in accordance with the load, and the converted power is supplied to the load.
In the case where a plurality of loads are connected to the load side of a rectifier 2 as shown in FIGS. 1A and 1B of the drawings of the present application, there is known a system of supplying power to the loads via a distribution panel provided with a wiring circuit breaker and a fuse as shown in Patent Document 2.